f(x)=(2cos^2 a/2-sina-1)/(sin(a+π/3)sin(a-π/3)
f(x)=(2cos^2 a/2-sina-1)/(sin(a+π/3)sin(a-π/3)
已知sina/cosa=-2,则sin(a-3π)+cos(π-a)/sin(-a)-cos(π+a)
已知f(x)=sin(a-3π)cos(2π-a)sin(-a+3π/2)/cos(-π-a)sin(-π-a)①化简f
已知f(x)=sin(π-a)cos(2π-a)tan(3π/2-a)/cos(-a-π)sin(-π-a)(1)化简f
在△ABC,sinA+cosA=1/3,-cos(3π-A)-sin(A-π)/sin(π/2+A)+sin(-A)的值
1- sin(2π/3 - a)/sina
在△ABC中,sinA+cosB=1/5,求cos(3π-A)+sin(A-π)/cos(π/2+A)+sin(5π/2
已知sina-2cosa=0求sin(π-a)cos(2π-a)sin(-a+2分之3π)除以tan(-a-π)sin(
已知f(a)=[sin(a-3π)cos^2(2π-a)sin(-a+3/2π)]/cos(-π-a)sin(-π-a)
已知f(a)=sin(a-3π)cos(2π-a)sin(-a+3π/2)/cos(-π-a)sin(-π-a)
sin(a+π/3)+sina= - 4根号3/5,则cos(a+2π/3)
已知sina+sin^2a=1,求3cos^2a+cos^4a-2sina+1